This invention relates to sialic acid derivatives and galactose derivatives, more particularly gangliosides and intermediate compounds for use in producing gangliosides, and to methods for producing the same.
Glycolipids found in mammal cells are glycosides between ceramides, which are sphingosines (long chain amino alcohols) to which aliphatic acids have been attached through an amide linkage, and one or more sugars such as glucose, galactose, N-acetyl glucosamine, N-acetyl galactosamine, fucose, sialic acid, etc. Among these glycosides, those containing sialic acid are called gangliosides.
Gangliosides exist mainly in the outer molecular layer of double molecular layers of the mammal cell membrane. Recent studies show that gangliosides play important roles in reception and recognition of, and response to, information in cells, receptor mechanism, differentiation, cell propagation, malignant cell transformation, cell behavior, etc.
However it is very difficult to isolate sialic acid residue-containing oligosaccharides from an organism. Therefore precise synthesis of such sialic acid residue-containing oligosaccharides is necessary for the elucidation of the precise correlation between biological information and the molecular structure of the oligosaccharides.